Miniature hand tool



y 1957 H. w. DEMLER 2,800,042

MINIATURE HAND TOOL Filed Nov. 10, 1953 5 Sheeis-Sheet l i -12 MIL-10INVENTOR i u I .fi'nry Wflemler 1/0 46 4'8 160M216 28 6%; BY 0 (i5 I04/J45 Ys July 23, 1957 H. w. DEMLER MINIATURE HAND TOOL 5 Sheets-Sheet 2Filed Nov. 10,, 1953 INVENTOR Q ",9."

w... H ry W Demlr B! I filia Vilm "I A OR Lm y 1957 H. w. DEMLER2,800,042

MINIATURE HAND TOOL Filed Nov. 10, 1953 5 Sheets-Sheet 5 47 INVENTOR '1Henry WDmZer July 23, 1957 H. w. DEMLER 2,800,042

MINIATURE HAND TOOL Fild Nov. 10, 1953 5 SheetsSheet 4 INVENTOR HenrWDemZer ATTOR July 23, 1957 H. w. DEMLER- 2,800,042

MINIATURE HAND TOOL Filed Nov. 10, 1953 5 Sheets-Sheet 5 l4 \7 4/4 Ii?89 36 IIIQ INVENTOR 88 Hnry W emlei' Un ted See Pe ToonHenryWfDemleij'Leb'auon; Pazyassignor to AMP lncorporatedya corporationof New Jersey Appiication'fibveinber 1'0. iysslsiriafNo. 391,269

6"Clfiili15; (Cl; 81""15) This invention relates to hand=operatedcrimping tools for crimping electrical connectors onto electricalconductors. Hand tools embodying the present invention can be usedtoapply a variety of different types" of crimp to a variety of dilferent'types of connectors. However, the utility of the present'tool can be'most conveniently pointed out with reference to atypical applicatioiiiofthe-to'ol and will be so dscribediri thepresent specification.

Such a typical application is illustrated in Figures 16 and 17 of'the'accompanying drawings Wherein'the' nunierahlO- designates a connectorc'omprisin'g' a tongue' portion 12' adapted to be secured to a" bindingp'ost'or the like and a'b'arrel portion 14'. 'l -henuniieral 16:generally designates an insulated conductor with the insulation strippedfrom anendpo'rtion 18 thereof. The bare end 18 and adjacentinsulated;portion of conductor 16 'are inserted in'the barrel 14, after whichth'ebarrel is c'rimpe'd to secure the connector to the end ofconductor'l. As shown in Figure 17 the barrel 14 of the connector iscrimped at two points 20 and 22; The crimp'20 provides a connectionbetween'the connector and the'b'are end '18 of conductor 16 and-thecrimp 22seals'th'e banel'14- to the insulation of conductor 16.

The crimping of such a connector to aconductorcan be effected by eitherapower-op'era'ted or ah'and operated tool and tools of both types'havebeen previously'proposed. For fixed installations power-operated toolsare generally preferred since they do not have thevpower limitationsof'hand-o'perated tool's. Onthe other' hand, there are many cases whereready portability and/ or economy are of paramount importance and in'these situations a manually operated tool is preferred. Thegeneralrequirements of such a hand-operated tool are: -(l)' that it belight in weight; (2) that'it be sufiicientl y strongs'tructurally towithstandtheusual crimping pressures; 3) that it be capable ofdelivering the desired relatively high crimping pressures by'a simplemechanical movement, e. g. the closure of a pair of handles and; (4)that it have a mechanical advantage such that thenecessary highcrimpingpressure can be delivereld by application of relatively little manualforce, e.- g. the force that can be conveniently applied by a Womanoperator. i

It is evident that the simplest way of increasing the mechanicaladvantageof a crimping tool is to increase the length of the handlesaiidin a nnniheief previously proposed toolsthis' hasbe'eu done. However, anincrease in the length of the handles also increases the weight of thetool which is undesirable. V 7

It is accordingly a priucipalobject of the present invention to providea hand tool which in relation to its weight has a substantiallyiiighe'rmechaiiieal advantage than the tools that have previously beenproposed. It is another object of the invention to rovide a hand toolthatis not only capable of developing desiredcriiriping pressures but isalso relatively light in Weight and-easily operable with one hand; I

Itis evidentthat the force required toefiect acrim varies as a functionof the exte'ht to which the crimping force need be appliedto-deform-th'ebarrel 14:

2 operationhas proceeded. For example, in the initial stages of thecrimping operationonly a relatively light 0n the dtherhand,-in the finalstages-"of the crimping operationa relatively large force is required toinsure a good electrical Contact between the barrel portion of theconnector and the conductor. The ideal crimping tool from thisstandpoint would be one wherein the application of a'continuous uniformmanually applied input force would produceat the 'crimping-diea forcethat varies in precise corr'espdndence Withtlie'forc'e requirements ofthe crimping operation. If, for example, the nature of the linkageusedin the tool is such thait it develops a'maximurn' force at the diewhen'iti's only partially closed, then'a larger-and heavier tool mustbeused to'efiect a given crimp: In lilremanner, if the nature of the-toollinkage is such that when'it'is, for example; half-closed itde'vel'ops'at the die a-force that-is low in r'elation to the forcerequired for the crimping operationg then a larger and heavier tool mustbe used t'o efie'ct afigiven crimp. It is accordingly 2.- further objectof the present-invention to provide a tool having an actuating-linkageor such a character that the application of a constant inputfor'ceproduce's at the crimping die a force-displacement relationshipwhich closely approaches the force displaceruent' requirements forcrimping aconneotor; Other objects of the invention will be in partobviousand inpart pointed out hereafter.

The'many objects and advantages of the presentinvention'can best beunderstood'by reference to the accompanying drawings which il-lustrateahandtool-incorporating a preferred embodiment of the invention andwherein:

Figure 1 is-a-side" elevation of the tool showing the generalarrangement of the handles aud crimping head as well as theratchet-mechanism interconnecting the handles;

Figure 2 is a top plan viewof the tool of Figure'l particularly showingthe l'ocatinghead' of the connector locat ing' mechanism, portions ofthe crimping mold adjusting mechanism; 7

Figure 3 'is a side elevation of the tool showing the reverse side fromthat illustrated in Figure 1-;

Figure-4 is a bottom view of the tool of Figure l;

Figure S'is a-vertical section taken on the line 5-5 of Figurel andparticularly showing-.thecrimping' molds;

Figure 6 is a vertical sectiontaken on the line 6-6 of Figure l andparticularly showing the configuration of the crimping dies that arelocated at the forward end of the; reciprocating plunger;

Figure '7jis a-horizontal section taken on the line 77 of Figure 5showing the reciprocating plunger in'ret-racted position and thelocating head of the locato'r mechanism in fullyadvanced'position; V V

Figure8'is asection 'on line 88-ofFigu're -7 showing details of thecrimping moldadjusting mechanism;

-F-igure- 9 is aperspective view-oia-portion of the crimping headshowing the crimping mold and disassembled components .of the crimpingmold adjusting mechanism; I v

Figures :10,- ll :and- 12 are vertical sections t aken on the lines10-10, 11"-11,- and.1-2- 12 of Figure; 6 vrespesti'vely; H

Figure 10 particularly includes a-side view of. the reciprocatingplunger and thecrimping molds anddies;

Figure 11 particularly illustrates the crimping ni'old adjustingmechanism p v Figure '12 particularly illustrates the details of theconiiector locating m 'echaiiis'in;

Figures 13, 14- and 15- comprise an exploded perspective View of thecentral portion 'of'the crimping head;

Fight-e13 shows the connector locator-nrechanism'stipporting block;

Figure -14 showst-he recipfocatorypliinge'r' with the criir'iping diesat-i-ts front end;

7 been crimped; and

V Figure 15 shows the plunger guide plate of the crimpcrimping molds anddies and showinga connector and V conductor in crimping position andalso the manner in which the locator mechanism locates the 'connectorforcrimping; V k

Figure 1 9 is a view similar to Figure 18 but with the parts inltheposition theyoccupy' after a connector has Figure 20 is a view generallysimilar to Figure 18 dentation in the center thereof whichcooperateswith the locating head of the locator mechanism to insure properpositioning of the connector for crimping.

Before proceeding to a detailed description of the structure shown inthe drawingspit seems desirable to point out that in achieving theobjectives of the present invention as outlined above two features ofthe present hand tool are particularly important. One of these is amanually operable quick-takeup link which moves the crimping die intoengagement with the connector before the handles are closed to performthe crimping operation proper, so that. the full movement of the handlesis available for performing the crimping operation itself, and so that arelatively wide angle between the handles can be used of this speciallinkage a force-displacement relation at V the leading. end of theplunger is obtained that more nearly approximates thetheoretically'ideal relation for the crimping of the connector. 7

Referring to the drawings and more particularly to Figure 1 the toolthere shown comprises a crimping head generally designated 24, a handle26 effectively integral with head 24 and a handle 28 pivota'lly securedto the head 24. The handles 26 and 28 are interconnected by a ratchetmechanism 30 which operates in such manner that once crimping of aconnector has started the handles 26 and 28 cannot again be opened untilthe crimping operation has been completed. Such ratchet mechanisms areknown in the art and hence need not be described in detail herein. 7 a 1Referring now particularly to Figures 7 and 14 of the drawings,longitudinally slideable in the crimping head 24 there is a reciprocableplunger 32 made up of the two plates 34 and 36 which are securedtogether and are provided at their forward ends with the wire crimpingdie 38 and insulation crimping die 40, respectively. The die 38 ispositioned to cooperate with a mold 42 formed 'but'showing'a tubularconnector having a positioning in- T in the crimping head (see also Fig.9) to crimp a portion 7, p

"of the connector onto the uninsulated end of the con- The die 40 ispositioned to cooperate with a.

ductor. crimping mold 44formed in the crimping'head 24 to crimp aportion of the connector onto the insulation of the conductor. As bestshown in Figures. 18 and 19,

the connector with the end of the conductorinserted' therein ispositioned between the crimping dies and crimping mold and the plungerisadvanced toward the crimping molds to cause the dies 38 and 40 tocooperate with the crimping molds 42. and 44 to crimp the barrel portion14 of the connector at two points as previously dehousing 46 thateffectively forms part of the crimping head. Nested within the housing46 there is a sub-assembly 47 that is particularly shown in explodedperspective view in Figures 1315. The sub-assembly 47 comprises ingeneral a locator mechanism supporting block 48 (Figure 13), the plunger32 (Figure 14) and the plunger guide plate 50 (Figure 15).

Portions of the plunger-actuating mechanism are also shown in Figure 14.Pivotally connected to the rear end of plunger 32 there is 'aquick-take-up link 52 that has a bifurcated upper end 54 which embracesthe rear end ofthe plunger and is pivotally secured thereto by a pin 53.The handle 28, which is of generally U-shaped cross-section, terminatesat its left end in a pair of ears 28a and 28b that embrace boththe link52 and the central portion of plunger 32. The ears 28a and 28b arepivotally connected to the link 52 by a pin 56.

It has been previously pointed out that handle 28 at its left-end is.pivoted to the crimping head. a This pivotal connection is establishedby means of a pin 58 (see Figure 13) which is mounted in the block '48and passes through ear 28b of handle 28, the plunger 32, ear 28a ofhandle 28 and plate 50. The plunger 32 (seeFigure 11) has a slot 59formed therein to permit reciprocating movement of the. plunger withrespect to pin 58. The assembled arrangement of the parts justdescribedis shown in Figures 6 and 7 of the drawings. 7

' Referring to Figures 6 and 9-11 of thedrawings and more particularlyto Figures 10 and 11, the crimping molds 42' and 44 are formed in acrimping mold sup-*- porting block 60 that extends into the housing 46.

More specifically and as best shown in Figure 6 the inner end of thecrimping mold block fits between the lowerpor a recess or track 68formed in the block 60. As best shown in Figure 8 both the member 66 andtrack 68 have upper and lower walls that diverge inwardly in such manneras to prevent movement of member 66 other than the desired slidingmovement along the track. The member 66 is positioned along track 68 toprovide a desired clearance between the insulation-crimping die andinsulation-crimping mold in a mannerthat will now be described.

Referring to Figure 8 aswell as to Figure 9, positioned within the'block60 there is a mold position adjusting pin 70 having a knurled knob 72 atits lower end. At its upper end the pin 70 is provided with a laterallyextending arm 74 adapted to engage one of a series of slots 76 formed inthe top of block 60 in such manner that the pin is latched againstrotation. A spring 78 interposed between the knob 72 and block 60 isbiased to urge the pin 70 downwardly and thereby urge the arm 74 intoone of the slots 76.

Near its upper end pin 70 is provided with two flat surfaces 80 and 82located at difierent distances from the center of the pin. As best shownin Figure 7 the pin is partially located within a recess 84 formed inthe member 66. .The construction is such that the pin 70 acts as a stopto limit outward movement of member 66 and thus of mold 44. When the pinis in the position shown in Figure 7 the periphery of the pin is adaptedto engage the inner edge of recess 84 and limit outward movement ofmember 66 when a connector is crimped. Inthis 1 position of pin 70 thereis minimum clearance between die 40 and mold 44. If it is desired toincrease the clearance between the insulation die and mold, the pin ismoved manually upward by means of knob 72 to release arm 74 from one ofthe slots76, and then rotated that hand tools incorporating the presentinvention are capable of achieving the several objects set forth at thebeginning of the present specification. By using the combination ofquick-take-up link and special linkage described above a smalllight-weight hand tool can be constructed which develops a surprisinglyhigh maximum crimping force. The quick-take-up link permits the use p ofa relatively wide handle opening since it provides a means whereby thepivot 53 can be shifted to the left (as viewed in Figure 1) before aneffort is made to close the handles. Also it permits the lost motion ofthe plunger to be taken up before starting movement of the handlesoccurs and hence a relatively large angular movement of the handles isavailable for a given displacement of the plunger. It has been foundthat by using the structure of the present invention hand tools can bemade no more than 6" long which develop sur prisingly high and quitesatisfactory crimping pressures.

It is of course to be understood that the foregoing description isillustrative only and that numerous changes can be .made in the,preferred embodiment described above without departing from the spiritof the invention.

For example, the quick-take-up link can be used in conjunction with alinkage other than the specific modified toggle linkage described andshown in the drawings. In like manner, by shifting the pivots 53 and 56,an operative tool can be made without using the quick-takeup link. Thepivot 58 can be spaced somewhat from the axis. of plunger 32, althoughpreferred results have been obtained by locating pivot 58 at or close tothe plunger axis, i. e. in substantial alignment with pivot 53 in thedirection of movement of the plunger. Other modifications within'thescope of the invention Will be apparent to those skilled in the art. 7 V

I claim:

l. A pair of relatively movable crimping members each of which isprovided with a crimping die, said dies being positioned to cooperate tocrimp a connector placed therebetween when said crimping members areforced toward each other, the die associated with one of said crimpingmembers being'formed on an adjustable support mounted in said'onecrimping member for sliding movement toward and away from the otherof'said dies, a die locating pin rotatably mounted in said one crimpingmember and having a series of flat surfaces located at difierentdistances from the axis of said pin and selectively positionable byrotation of said pin to engage and limit sliding movement of saidadjustable support, whereby said pin can be selectively rotated to'vary' the crimping location of said adjustable support, and means forforcing said crimping members together to crimp a connector placedbetween said dies.

2. In a hand tool for crimping electrical connectors in combination, acrimping head having a first crimping die therein, a crimping membermovably mounted in said head and having a second crimping die positionedto cooperate with said first dieto crimp a connector placed between saiddies, said first die being formed on an adjustable support slidablymounted insaid'crimping head for movement toward and away from saidsecond: die, means for applying power to said movable crimping g amember to force said second die toward said first die to crimp aconnector placed between said dies, and a dielocating pin rotatablymounted in said head in the path of said adjustable support andpositioned to engage and limit sliding movement of said support, saidpin having a series of flat surfaces located at different distances fromthe axis of said pin whereby said pin can be selectively rotated to varythe crimping position of said first die.

3. A hand tool according to claim '1 and wherein said die-locating pinis provided with a laterally extending finger selectively engageablewith one of a series of slots formed in said crimping head to insureproper positioning of said pin with respect to said adjustable support.

4. A hand tool according to claim 3 and wherein said die locating pin isaxially biased by a spring to maintain said finger in one of said slotsand permit axial movement of said pin against the biasof said springwhen'it is desired to disengage said finger from said slot to adjust therotational position of said pin.

5. In a hand tool for crimping electrical connectors in combination, acrimping head having a first crimping die therein, a crimping membermovably mounted in said head and having a second crimping die positionedto cooperate with said first die to crimp a connector placed betweensaid dies, means for applying power to said movable member to force saiddies together to crimp a connector therebetween, and aconnector-locating device mounted in said head for sliding movementtherein, said locator device including a locating head having aprojection extending therefrom and adapted to engage a notch in aconnector to position the connector for crimping, spring-meanseffectively inter-posed between said crimping-head and locator-head tourge said locator-head into registry with said first die, and a manuallyoperable member for retracting said locating head against the action ofsaid spring-means.

.6. In a hand tool for crimping electrical connectors in combination, acrimping head having acrimping mold therein, a plunger mounted forreciprocating motion in said head and having a crimping die positionedto cooperate with saidv mold to crimp a connector placed in the path ofsaid plunger, a pair of handles connected to said head and plunger andrelatively movable to'reciprocatesaid plunger, and a connector-locatingdevicefor properly locating a connector between said die and mold,- saidlocating device including a shaft mounted for'axial sliding movement insaid crimping head, a locator head at one end of said shaft, said headhaving a projection extending therefrom that is adapted to engage anotch in a connector to position the connector for crimping, a

compression-spring bearing at its ends against said crimp ing head andshaft and biased to urge said locator-head into registry with saidcrimping mold, and a finger-piece 'eifectively connected to said shaftfor retracting said locator-head to permit insertion of a connector intosaid tool.

References Cited in the file of this patent UNITED STATES PATENTS455,183 Du Shane "June 30, 1891 1,613,715 Matson Jan. 11, 1927 2,329,385Bratz Sept. 14, 1943 2,359,083 Carlson Sept. 26, 1944 2,544,329 KirkMar. 6, 1951 2,565,983 Nelson Aug. 28, 1951 2,574,811 Blumensaadt Nov.13,1951

FOREIGN PATENTS 86,362 Austria May 15, 1921

